Rotary pump or motor



July 7, 1964 w. H. WILKINSON 3,139,835

ROTARY PUMP OR MOTOR Filed Aug. 15, 1962 9,Sheets-Sheet 1 INVENTOR WILLIAM H. WILKINSON July 7, 1964 w. H. WILKINSON ROTARY PUMP OR MOTOR Filed Aug. 15, 1962 9 Sheets-Sheet 2 INVENTOR. WILL/AM H W/L K/NSO/V July 7, 1964 w. H. WILKINSON 3,139,335

ROTARY PUMP 0R MOTOR Filed Aug. 15, 1962 9 Sheets-Sheet 3 INVENTOR WILLIAM H. WILKINSON Fla 5 m m AW July 7, 1964 w w mso 3,139,835

ROTARY PUMP OR MOTOR Filed Aug. 15, 1962 9 Sheets-Sheet 4 INVENTOR W/LL /A M h. W/L KIA/SON July 7, 1964 w. H. WILKINSON 3,139,835

ROTARY PUMP 0R MOTOR Filed Aug. 15, 1962 9 9 Sheets-Sheet 5 INVENTOR. WILLIAM H. W/L KIA/501V FIG. 9 g mww July 7, 1964 w. H. WILKINSON 3,139,835

ROTARY PUMP OR MOTOR Filed Aug. 15, 1962 9 Sheets-Sheet 6 v a!!! W@ INVENTOR WILL/AM h. WILKINSON Mfmwa D y 1964 w. H. WILKINSON 3,139,835

ROTARY PUMP OR MOTOR Filed Aug. 15, 1962 9 Sheets-Sheet 7 INVENTOR. WILL/AM H. WILKINSON UMAOXW JA' b m July 7, 1964 w. H. WILKINSON 3,139,835

ROTARY PUMP OR MOTOR Filed Aug. 15, 1962 9 Sheets-Sheet 8 INVENTOR W/L LIAM H. W/L Kl/VSO/V y 1964 w. H. WILKINSON 3, ,83

ROTARY PUMP OR MOTOR Filed Aug. 15,- 1962 9 Sheets-Sheet 9 IN VENTOR. WILL/AM h. W/L K/NSO/V United States Patent 3,139,835 ROTARY PUMP 0R MOTOR William H. Wilkinson, Columbus, Ohio, assignor, by mesne assignments, to Davey Compressor Company, Kent, Ohio, a corporation of Ohio Filed Aug. 15, 1962, Ser. No. 217,046 23 Claims. (Cl. 103126) This invention relates to rotary pumps and motors, and, more particularly, to a rotary pump in which rotatable elements provide a plurality of fluid compartments of continuously varying dimensions. This invention is a continuation in part of copending application Rotary Pump or Motor, Serial No. 64,813, filed October 25, 1960, now abandoned, and includes the invention therein and a number of improvements thereon.

In the type of apparatus herein disclosed, an inner rotary member having outer teeth is arranged eccentrically within and meshing with an outer annular member having inner teeth, the axes of the two members being parallel. The inner member has preferably one tooth less than the outer member. In one embodiment, one of the members is rotated and the meshing member is also rotated so that the two members act as a gear pair. Rotative power may be applied to either member or both. In a second embodiment, the inner member rolls around the inside of the outer member with either pure rolling motion or a combination of rolling and rotating motion.

Pumping devices having two rotors meshing like a gear are well known in the art and many improvements thereon have been proposed. Such improvements may concern tooth configurations, sealing of the rotating parts, and, in general, various features intended to add to the efliciency of the apparatus. One of the main disadvantages of the conventional pump of this type is the friction that occurs between the meshing teeth, the rotating elements, and the housing provided for these elements. This invention includes a porting system and other improvements that not only solve many of the difiicult porting problems present in this type of apparatus, but also reduce the friction between the various moving parts.

The outer rotor generally comprises a circular ring or cylinder that is annularly toothed so as to form a plurality of inwardly projecting rounded teeth with intervening valley or concave portions. With this outer rotor construction and with teeth of the inner rotor engaged about its periphery, upon rotation of one of the rotors to drive the other, a constant but slow gain in revolutions occurs between the two rotors. The teeth of the inner rotor remain at all times in contact with the outer rotor and, thus, define a plurality of compartments of continually varying dimensions.

In the past, the use of intermeshing gear teeth to pump fluid has been developed to a present construction whereby a plurality of separate compression or pumping compartments is defined between tooth portions of inner and outer intermeshing pump rotors that rotate about fixed axes. The pumping action is based fundamentally on the relative rotation occurring between the inner and outer rotors as a result of having teeth of the inner rotor one less in number than the corresponding teeth and recesses of the outer rotor. Upon rotation, the external and internal teeth mesh as both the inner and outer rotors turn; the teeth and the gullets of the rotors fit together at one portion of the circle but separate in a large part of the circle opening up to form a compression chamber sucking fluid in through an intake, and then closing in on the entrapped fluid to compress it and discharge it.

With proper design, the compartments between inner and outer rotor teeth receive a fluid such as air or liquid through a suitable port at a point when the compartments are approaching their greatest dimension; then, in subse- 3,139,835 Patented July 7, 1964 quent phases of any particular revolution of the rotors, the several compartments decrease in dimension to a minimum, thereby compressing the fluid contained therein. A suitable port is usually provided adjacent the region of minimum dimension through which the compressed fluid is discharged.

Pumps of this type have received widespread acceptance in the art. They are compact, simple, and, since they have a small number of moving parts, display long Wear and require little maintenance, repair, and supervision. Despite the manifest advantages of the construction just described, however, it will be noted that, as the rotors are necessarily enclosed in a suitable housing, there is contact between the external running surface of the outer rotor and the housing, the cooperating parts of the inner and outer rotor, and the ends of the rotor against their sealing and retaining end plates, all of which are frictional and sliding in nature. Heretofore, the friction developed in this type of pump has, to a certain extent, limited the speed of rotation and the capacity and efliciency of the pump. An important advantage of the apparatus of this invention then is to reduce the friction between the moving parts, allowing greater speed, providing greater capacity, reducing wear, and minimizing frequent replacement of parts.

Briefly described, a specific example of the apparatus of this invention includes a gear pump having a rotary gear element meshing with an internal ring gear element, including a porting system, comprising passages between the teeth of the internal ring gear alternately communicating with inlet chambers provided with a common inlet duct and exhaust chambers provided with a common exhaust duct.

Another example of the apparatus of this invention includes a gear pump having a rotary gear element meshing with an internal ring gear element disposed in a housing to form varying sized chambers and a flexible band in contact with at least half of the periphery of the ring gear and spaced therefrom for the remaining portion, first ports in the pumping chambers sealed by the flexible band in the area that is in contact with the periphery of the ring gear and the first ports communicating with a passage in the housing at the position where the flexible band is spaced away from the periphery of the ring gear, and second ports positioned to provide communication between the varying sized chambers during expansion of the varying sized chambers and a source of fluid exterior to the device.

One advantage of the present invention is the reduction of friction, as previously mentioned. Another advantage is the arrangement of a porting system that provides twostage compression within a single pumping unit. Among other advantages of the present invention, as compared to conventional pumps, are increased pressure, capacity, and efficiency. Still other advantages of the invention are apparent from the following specification, the drawings relating thereto, and the claims herein set forth.

In the drawings:

FIGS. 1 and 2 are corresponding sections taken along the lines 1-1 and 2-2 of the apparatus according to this invention;

FIG. 3 is an exploded isometric view of the main component elements of the apparatus illustrated in FIGS. 1 and 2;

FIG. 4 is a sectional view showing the end plates of the housing attached to the port ring;

FIGS. 5, 6, and 7 are sectional views of the invention in various stages of planetary movement and with the port ring afiixed to the housing;

FIGS. 8 and 9 are corresponding sections of the invention taken along the lines 8-8 and 99 also constructed for planetary movement and with the ring afiixed to the housing;

FIG. is a cross-sectional view of the invention constructed for use as a two-stage compressor.

FIG. 11 is an exploded isometric view of the main component elements of another example of the apparatus according to this invention;

FIG. 12 is a cross-sectional view of the apparatus according to FIG. 11;

FIG. 13 is an elevation view of one end of the apparatus according to FIG. 12 with a different arrangement of intake ports; and

FIGS. 14 and 15 are corresponding sections of the invention taken along the lines 14-14 and 15-15 showing another type of port construction.

In the drawings, the same reference numerals are applied to identical parts in all embodiments, and such identically numbered parts are substantially identical in structure, function, and operation. Therefore, to eliminate confusing duplication, these parts, their interrelationship and their function, will be described only in conjunction with a single embodiment, such description applying to all embodiments where these parts appear.

In the description that follows, only the major features of the apparatus are discussed. The more detailed features that add to efficient and competent operation, such as packing and sealing material, bearings, and oiling mechanisms are, for the most part, neglected, to avoid confusion and needless complication of the description.

Referring now to FIGS. 1, 2, and 3, the motor or pump 11, comprises a housing 13, a rotatable group of chambers therein called a port ring 15, an annular rotor or female ring gear 17, and an inner rotor or male pinion 19.

The housing 13 includes a casing 21 having a central bore 23 and flanges 25 and 27 at each end. Attached to the flanges 25 and 27 by suitable means, such as bolts 29-29, are end walls or end plates 31 and 33. On the sides of the end plates 31 and 33 (the end plates could, of course, rotate and be attached to either the pinion or the ring gear), at the outer periphery, are an intake duct 35 and a discharge duct 37, respectively.

The port ring 15 is attached to a circular disk 38 and is divided into a plurality of chambers or ports having three sides. A fourth or peripheral side of the ports is closed by contact with the bore 23 of the housing 13, while the fifth or inner side is closed by the periphery of the annular rotor or ring gear 17. The remaining side of the port remains open so that the ports communicate with either the annular discharge passage 39 or the annular intake passage 40, depending upon which side of the chambers is open. Naturally, the ports need not take a particular shape as long as they communicate with the periphery of the annular rotor or ring gear 17 and the annular discharge passage 39 or annular intake passage 40. Each of the discharge ports 41-47 is paired with one of the intake ports 51-57. Each pair of ports is separated by one of the solid partitions 61-67 and each discharge port 41-47 is separated from its corresponding intake port 51-57 by a solid partition 71-77. The partitions 61-67 between pairs of ports are of greater arcuate length than the partitions 71-77 between intake and discharge ports.

The annular rotor or ring gear 17 has a plurality of teeth 81-86 with gullets or valleys 91-96 between successive teeth. Each valley has a communicating passage or communication means 101-106 from the bottom of each valley 91-96 to the outer periphery of the ring gear 17.

The inner rotor or pinion 19 also has a plurality of teeth 111-115. The pinion 19 is connected to and rotated by a shaft 131. Adjacent to the pinion 19 and attached to the shaft 131 is an external gear 133 that meshes with an internal gear 135 on the disk 38 of the port ring 15. The pinion 19 rotates about its axis 137 while the ring gear 17 and port ring 15 rotate about an axis 138 that is spaced from and parallel to axis 137. The shaft 131 passes through and is supported by bearing 139 in the end plate 33.

In the specific example of the apparatus shown in FIGS. 1, 2, and 3, it will be seen that there are five teeth on the pinion 19, six teeth on the ring gear 17, and seven pairs of inlet and discharge ports on the port ring 15. The gear ratio between gears 133 and 135 is five to seven. The gear ratio between the pinion 19 and ring gear 17 is five to six. For every six revolutions made by the pinion 19, the ring gear 17 makes five revolutions and for every seven revolutions of the pinion 19, the port ring 15 makes five revolutions. The result of the gear ratios is that on each revolution of the pinion 19, each tooth 111-115 advances in the direction of rotation from one valley 91-96 to the next valley 91-96 of the ring gear 17; and on each revolution of the ring gear 17, each communication means 1111-106 advances in the direction of rotation from an area opposite one pair of ports to an area opposite the next pair of ports on the port ring 15. As the pinion 19 is rotated about the axis 137, the pumping chambers 141-146, formed between the pinion 19 and ring gear 17, are changing in size. The communication means 101-106 are therefore indexed opposite a discharge port at reduction or decrease in size of the pumping chambers 141-146 and are indexed opposite an intake port at increase in size of the pumping chambers 141-146.

Assuming thatthe pinion 19 is rotated clockwise, as it is shown in FIG. 1, it will be seen that the tooth 112 is leaving the valley 92 and that the pumping chamber 142 is undergoing expansion. Compressor fluid is introduced into the pumping chamber 142 through a passageway from the intake duct 35 established through the annular intake passage 40, the intake port 52, and the communication means 102. In like manner, the tooth 113 is leaving the valley 93 so that the pumping chamber 143 is undergoing expansion with compression fluid entering through the intake duct 35, the intake passage 40, the intake port 53 and the communication means 103. The pumping chamber 144 is fully expanded and is about to undergo compression. The communication means 104, which presently communicates with the pumping chamber 144, is moving away from the intake port 54 to be closed by the partition 65 and the tooth 113 is about to enter the valley 94. The tooth 114 is entering the valley compressing fluid in the pumping chamber 145. The communication means is still closed by the partition 66, but on further rotation will overtake the discharge port 46, whereupon the compressed fluid will be discharged through the communication means 105, the discharge port 46, the annular discharge passage 39, and the discharge duct 37. The pumping chamber 146 is still further reduced in size as the tooth enters the valley 96 and compressor fluid is exhausting through the communication means 106, the discharge port 47, the annular passage 39, and the discharge outlet 37. The pumping chamber 141 that exists between the tooth 111 and the valley 91 has been reduced to a minimum so that compression and discharge have been completed. The port 101 is passing across the partition 71 as it moves from the discharge port 41 to the intake port 51. The tooth 111 will leave the valley 91 enlarging the pumping chamber 141 as rotation continues with compressor fluid entering through the intake port 51 and the communication means 101.

Ideally, of course, each communication means 101-106 should be slightly narrower than each partition 71-77 so that as the communication means 101-106 pass the partition 71-77 they will be blocked off briefly rather than allowing compressor fluid in the discharge ports 41-47 to pass around the edge of the partition 71-77 through the communication means 101-106 into the adjacent intake ports 51-57. Also, re-expansion may be necessary before the communication means 101-106 establish communuication with the intake ports 41-47. As shown in this example, the larger partitions 61-67 block off the communication means 101-106 during the first part of compression in the pumping chambers. The partitions 61-67 should be sized according to the intended use of the apparatus. For example, if the compressor fluid is to be an incompressible fluid, the partitions 61-67 should be thinner to allow an earlier discharge of the fluid from the pumping chambers.

Additional friction may be eliminated by having the end Walls or end plates rotate as shown in FIG. 4. The end plates are attached to the pinion 19, ring gear 17 or port ring 15. In FIG. 4, the original end plates 33 and 31 are removed. The disk 38 of the port ring serves as one end plate, and the other end plate 31 is attached to the port ring 15. The end plate 31 is about the same size as the ring gear 17 and is provided with tabular extensions 32-32 that coincide with the partitions 61-67 of the port ring 15. The end plate 31 is attached to the port ring at the partitions 61-67 by suitable means such as threaded fasteners 34-34 (only one fastener 34 is shown in FIG. 4).

In the example of the apparatus just described, the housing 13 is firmly anchored to a suitable base (although no mounting brackets are shown) and each rotor rotates about its own axis while the axes are held fixed. The tooth tips of the pinion 19 meet the bottoms of the valleys of the ring gear 17 at the same location opposite a nonmoving point on the housing. Compression occurs in the pumping chambers on one side of a plane intersecting this nonmoving point and the axes 137 and 138, with the axes 137 and 138 lying within the plane. Expansion in the pumping chambers takes place on the opposite side of this plane.

Referring to FIGS. :5, 6, and 7, when the port ring 15 is not rotated or is fixed as a part of the housing 21 and the axis 137 of the pinion 19 moves in a circle in one direction about the axis 138 of the ring gear 17 as both the pinion 19 and ring gear 17 rotate about their respective axes 137 and 138 in the opposite direction, a planetary movement of the pinion 19 in ring gear 17 is obtained. This results in still less friction than the movement previously described. The pinion 19 rolls around the inside of the ring gear 17 and the ring gear rotates at a much slower speed. In the example previously discussed, each pumping chamber expands and compresses once for each rotation of the ring gear 17. However, when the movement of the pinion 19 is changed to planetary and has the gear ratios of the example described, the pumping chambers expand and compress seven times for each revolution of the ring gear 17, that is, once more than the number of teeth contained in the ring gear.

Referring to FIG. 5, the external gear 133 on the pinion 19 rolls around the internal gear 135 on the disk 38 of port ring 15. Since the port ring is afiixed to the housing, the gear 135 is effectively mounted on the housing. Assuming that this direction is counterclockwise, then the axis 137 of the pinion 19 moves in a circle counterclockwise with the axis 138 of the ring gear 17 as the center of the circle. At the same time, the pinion 19 rotates clockwise about its own axis 137 which rotates the ring gear 17 clockwise about its own axis 138. The port ring 17 in this instance is held stationary and is made a part of or afiixed to the housing 21 of the pump 11. The pinion 19 must be rotatably mounted on a crank as shown in FIG. 8 and subsequently described.

Comparing FIG. 5 to FIG. 6, it will be seen that in FIG. 6 the pinion axis 137 has moved counterclockwise about the ring gear axis 138 through an angle of about 100 degrees. The pinion 19 has rotated about 45 degrees and the ring gear 17 about degrees, both in a clockwise direction. The fluid in the chamber 142, between the tooth 112 and the valley 92, which was undergoing expansion in FIG. 5 is about to undergo compression in FIG. 6 as the tooth 111 moves into the valley 92. Compressor fluid is drawn into the chamber 142 through the inlet port 52 and the communication means 102. The communication means 102 has moved so that it has now almost completely passed the inlet port 52 and is about to pass over the partition 63. It will be further seen that in FIG. 7, the axis 137 has moved counterclockwise in excess of 180 degrees, the pinion 19 has rotated clockwise almost degrees and the ring gear 17 has rotated clockwise almost 45 degrees. The fluid in the chamber 142 between the tooth 111 and the valley 92 has undergone compression and is (in FIG. 7) discharging fluid through the communication means 102 into the discharge port 43, the communication means 102 having passed the partition 63.

A further comparison of FIGS. 5, 6, and 7 reveals that the fluid in pumping chamber 143 which is formed by the tooth 113 and the valley 93, is being expanded in FIG. 5 being compressed as the tooth 112 enters the valley 93 in FIG. 6, and is subsequently reduced to a minimum in FIG. 7. During enlargement of the chamber 143, as shown in FIG. 5, fluid is being drawn into the chamber 143 through the intake port 53, is compressed in FIG. 6 with the communication means 103 opposite the partition 64, and in FIG. 7 the chamber 143 has been reduced to a minimum with the fluid having been passed into the discharge port 44 through the communication means 103.

The comparison of FIGS. 5, 6, and 7, then, shows that the chambers 141-146 are reduced to a minimum and reformed in succession as the pinion axis 137 is rotated about the ring gear axis 138. The rotation of the ring gear 17 moves the communication means 101-106 opposite the intake ports 51-57 and discharge ports 41-47 at the proper time to allow compressor fluid to enter or to leave the pumping chambers 141-145 as they continuously change in dimensions. The end plates may, of course, be constructed so as to rotate with the ring gear 11 and the pinion 19 as was previously shown and described.

It is also possible to keep the ring gear 17 stationary as the pinion rolls around the internal surface of the ring gear 17. FIGS. 8 and 9 show an example of the device, according to the invention, having the ring gear 17 attached to or made a part of the end plate 31. When the ring gear 17 is fixed or nonrotatable, the port ring 15 must be rotated to produce proper indexing of the communication means 101-106, the intake ports 51-57, and discharge ports 41-47. Therefore, in FIGS. 8 and 9 the port ring 15 is separate from the housing and free to rotate while the ring gear 17 is fixed. The pinion 19 is rotatably mounted by suitable means, such as bearings 132 132, on an eccentric 134 mounted on shaft 131. The indexing or proper timing between the port ring 15 and communication means 101-106 is established by the meshing of gear 133 (attached to the pinion 19) and gear 135 (attached to the port ring 15) as the chambers 141- 146 enlarge, an intake port 51-57 is positioned opposite the appropriate communication means 101-106, and, as the chambers 141-146 are reduced to a minimum, a discharge port 41-47 is positioned opposite the appropriate communication means 101-106.

A modification of the device that utilizes the planetary movement (FIGS. 5, 6, and 7) and has a fixed port ring 15, is shown in FIG. 10. In FIG. 10, the pump housing or casing has been omitted to avoid confusion and to allow a simplified explanation of the porting system. In this embodiment, the gear 135 is afiixed to the housing so that the pinion and ring gear are properly indexed with relation to the ports 41-47 and 51-57. The ports, which are in the same positioned arrangement as those formerly discussed, are ducted so that two-stage compression is obtained. To obtain a two-stage compressor, the discharge ports 41, 42, 43, 44, and 45 are connected to a distribution duct 161. The distribution duct passes the first-stage compressed fluid from the discharge ports 41-45 to the intake ports 55 and 56. The pumping chambers 141-146 that obtain their intake fluid from the intake ports 55 and 56 compress the fluid again to supply secondstage compressed fluid to the discharge ports 46 and 47. A collector duct 162 is provided to contain and pass the second-stage compressed fluid to a common discharge duct 163. The intake ports 51, 52, 53, 54, and 57 receive lowpressure fluid through intake ducts 165, 166, 167, 168, and 164, respectively.

- If the two-stage compressor is an air compressor, the intake ducts 164-168 will be open to the atmosphere. For example, in a two-stage air compressor at the position of the apparatus as shown in FIG. 6, the pumping chamber 144 receives atmospheric pressure air through the intake duct 168, the intake port 54, and the communication means 104. The atmospheric pressure air is compressed to the first stage as the tooth 113 enters the valley 94 and is then discharged through the communication means 104, the discharge port 45 and then into the distribution duct 161 that supplies first-stage compressed air to intake ports 55 and 56. The pumping chamber 145, which obtained first-stage compressed air from intake port 55, is compressing the first-stage compressed air to the second stage of compression. The second-stage compressed air is then discharged through the communication means 105, the discharge port 46, and into the collector duct 162 that supplies second-stage compressed air at the discharge duct 163.

The size of the partitions 61-67 and 71-77, intake ports 51-57 and discharge ports 41-47 may be varied to obtain proper volume relationships so that the desired pressures and flow rates for two-stage compression are maintained. It will be seen that, in addition to the variations that may be made in the number of teeth and ports, the possible connections and combinations of connections between the numerous ports allows numerous stages of compression. This is possible. because the planetary movement of the pinion 19 and the plurality of ports makes each pumping chamber, in a sense, an isolated pump. This isolated pump may be engaged in a different stage of compression on difl'erent pumping cycles, depending upon the air supplied to it on intake by the intake port. A further feature is to insert heat exchangers into the distribution ducts and obtain intercooling between stages of compression.

FIGS. 14 and 15 show a pump or motor construction according to the invention, wherein the outer annular rotor 17 is made a part of or affixed to the housing 13 and end plates 31 and 33. The pinion 19 rolls around the inside of the ring gear 17 in the same manner as previously described herein for the construction shown in FIGS. 8 and. 9 wherein the ring gear 17 was also fixedly mounted with respect to the housing 13. The port ring 15 (FIGS. 8 and 9) is eliminated and replaced by a plurality of plug valves 171-176 in FIGS. 14 and 15. Except for the specific construction of the parts, the pump shown in FIGS. 14 and 15 operates like the form shown in FIGS. 8 and 9.

The drive shaft 177 is rotatably mounted in end plates 31 and 33 by suitable means such as bearings 178-178. Two eccentrics 179-179 are afiixed to the shaft 177. The pinion 19 is rotatably mounted on the eccentrics 179-179 by means of bearings 180-180. The axis 137 of the pinion coincides with the centers 181-181 of the eccentrics 179-179. One revolution of the axis 137 causes the pinion 19 to roll once around the surface of the ring gear 17.

The plug valves 171-176 are each provided with an intake slot 182 and a discharge slot 183. At the end of shaft 177 is a gear 184 that drives a plurality of timing gears 185-185 (rotatably mounted between the end plate 31 and a gear cover plate 186) which in turn rotate the plug valves 171-176 by meshing with a gear 187 on the end of each plug valve 171-176. The intake slots 182 provide communication between the communication means 101-106 and the annular intake passage 40 during increase in size of the varying sized chambers 141- 8 146. Likewise, the discharge slots 183 provide communication between the communication means 101-106 and the annular discharge passage 39 during decrease in size of the varying sized chambers 141-146.

The gear ratio of gears 184, 185, and 187 are such that the shaft 177 rotates two times while the plug valves 171-176 rotate once. Assuming that shaft 177 rotates in a clockwise direction, then the pinion 19 rolls around the ring gear 17 in a clockwise direction and the plug valves 171-176 rotate in a clockwise direction. As shown in FIG. 15, the discharge slot 183 of plug valve 171 is just moving out of alignment 'with the communication means 101 as the chamber 141 has been reduced to a minimum. Intake slot 182 of plug valve 172 is moving into alignment with communication means 102 as chamber 142 begins to enlarge. Note that the plug valves 171-176 must rotate at half the shaft speed since the slots 182-182 and 183-183 are aligned with the communication means twice during each revolution. Each communication means 101-106 is divided by a partition 189 to help seal the plug valves 171-176 and prevent leakage between the discharge and intake sides of the apparatus.

Another example of the apparatus is shown in FIGS. 11 and 12. The pump 211 is comprised of a housing 213, a flexible band 215, an outer annular rotor or ring gear 217 and an inner rotor or pinion 219.

The housing 213 includes a cylindrical casing 221 having a central bore 223, a flange 225, and an end plate 231. Attached to the flange 225 by suitable means, such as bolts (not shown), is a removable end plate 233. On the outer periphery of cylindrical casing 221 is a dis charge duct 237.

The flexible band 215, encircles a portion or at least half of the periphery of the ring gear 217 passing under the idler rollers 239 and 241 which help hold the band 215 against the periphery of the ring gear 217. The idler roller 243 is positioned at a greater radial distance from the ring gear axis 345 than the idler rollers 239 and 241, so that passing the band over the idler roller 243 spaces the band 215 away from the periphery of the ring gear 217 between the idler rollers 239 and 241. Between the band 215 and the central bore 223 is an annular discharge space or passage 247.

The ring gear 217 is much like the ring gear previously discussed in FIGS. 1 through 5, having a plurality of teeth 281-286 with a gullet or valley 291-296 between successsive teeth. A plate 298 has been added to one side of the ring gear 217. Each valley 291-296 has a passage or discharge port 301-306 from its bottom to the periphery of the ring gear 217. In the constructions of FIGS. 1-6, these passages allowed compressor fluid to pass in both directions, but in this construction, they are used for discharge, unless, of course, the apparatus is to be a motor. A shaft 308 is connected to the plate 298 of the ring gear 217, passes through an opening 309 in the end pltae 231 of the housing 213, and is free to rotate within the bearing 310.

The pinion 219 has a plurality of teeth 311-315 and is connected to and rotated by a shaft 317. The shaft 317 passes through an opening 318 in the removable end plate 233 and is free to rotate within the bearing 319.

Assuming that the pinion 219 is rotated clockwise, as it is shown in FIG. 11, it will be seen that the pumping chambers 321-326 are formed, expanded, and compressed in the same manner as the apparatus in FIGS. 1-3, with the pinion 219 and ring gear 217 each rotating about their respective fixed axes 327 and 345. FIG. 12 shows the pumping chambers 322 and 323 expanding when they are opposite the intake port 329 (shown in FIG. 11) positioned in the end plate 233. Port 329 is located inside the circle of the flexible band 215 so that compressor fluid may be passed directly into the enlarging pumping chambers. As the pumping chambers move further in a clockwise direction, they get smaller and are sealed by the contacting teeth of the pinion 219, ring gear 217, and by the end plates 298 and 233 which contact the ends of the pinion 219. The discharge ports 301-305 (as shown in FIG. 12) are sealed by the flexible band 215 while discharge port 306 is discharging into the annular discharge passage 247. The flexible band 215 covers the discharge ports 301-306 leading to the pumping chambers, except for the area between the points substantially opposite the idler rollers 239 and 241; therefore, the band is pressed against the discharge ports 301-306 during the time that they are opposite a pumping chamber that has a lower pressure than the pressure of the annular discharge passage 247. Sealing of the discharge ports 301-306, therefore, does not depend entirely on tension of the band 215. The band 215 should, of course, have enough tension to keep it in close contact with the periphery of the ring gear 217 so that it is readily available to seal the discharge ports 301-306.

The flexible band 215 moves at the same speed as the periphery of the ring gear 217 so that the friction is reduced further in this example of the apparatus, since the pumping parts have a friction developed similar to that of gear and belt-type friction with sliding friction eliminated except for the necessary supporting bearings. Air enters through the intake port 329 into the pumping chambers 321-325 as they are expanded, passes around with the rotation of the pinion 219 and ring gear 217, is compressed and discharged at the space between the flexible band and the periphery of the ring gear into the annular discharge passage 247, and may be utilized at the discharge outlet duct 237. The flexible band 215 is slightly narrower than the space between the end plates 231 and 233 so that the discharge air can flow between the edges of the band 215 and the end plates 231 and 233 into the discharge passage 247.

FIG. 13 shows another arrangement for introducing the intake air into the pumping chambers. The apparatus has the same pinion 219, ring gear 217, and flexible band 215 constructions and relationships as in FIGS. 7 and 8. The difference is that an end plate 351 is attached to and rotates with the pinion 219. This construction eliminates the friction between the end of pinion 219 and an end plate, and reduces the friction between the ring gear 217 and the end plate that exists in the construction of FIGS. 11 and 12 where the end plate 233 is fixed and does not rotate.

A plurality of intake ports 361-365 (in the preferred embodiment the number of intake ports will equal the number of teeth on the pinion 219) are positioned to communicate through the rotating end plate 351, by having the center of rotation of the end plate 351 the same as the pinion 219, namely the pinion axis 327, the intake ports 361-365 are opposite the valleys 291-296 during part of the pinion 219 revolution and opposite the teeth 281-286 during the remaining part of the pinion 219 revolution. It will be seen in FIG. 9 that port 361 is just passing from opposite tooth 282 to the valley 292 to communicate with pumping chamber 322, which is undergoing expansion. Port 362 is opposite valley 293 and is supplying pumping chamber 323 with compressor fluid. Port 363 supplied pumping chamber 324 with compressor fluid during expansion and is now sealed by tooth 285 so that pumping chamber 324 may be compressed as the pinion 219 and ring gear 217 continue their rotation.

An annular ring 371 is aflixed to the pump casing by suitable means such as bolts 372 and has a lip 373 that overlaps the outer edge of rotating end plate 351 so that exhaust passage 247 may remain sealed.

While there has been illustrated and described herein the preferred embodiment of the apparatus in more or less detail, it is realized that various modifications of the invention may be made without departing from the spirit and scope thereof and without the exercise of further invention. No attempt is here made to exhaust all such possibilities. It will be understood that the words used herein are words of description, rather than of limitation,

and that various changes may be made without departing from the spirit or scope of the invention herein disclosed.

What is claimed is:

1. In a rotary pump or motor, the combination of:

(a) a rotary gear element;

([2) an internal ring gear element meshing therewith to form varying sized chambers between the outer periphery of said rotary gear element and the inner surface of said internal ring gear element;

(0) a porting construction comprising a communication means between successive teeth of said internal ring gear element, said communication means communicating between the inner surface and the periphery of said internal ring gear element, an annular ring contacting the periphery of said internal ring gear element, a plurality of discharge ports and a plurality of intake ports, said discharge ports being alternately arranged with said intake ports in said annular ring, and means on said annular ring for positioning a discharge port in communication with each said communication means on decrease in size of said varying sized chambers and for positioning an intake port in communication with each said communication means on increase in size of said varying sized chambers.

2. In a rotary pump or motor, the combination of:

(a) a housing;

(b) a rotary external gear element;

(0) an internal gear element meshing with said external gear element to form varying sized chambers between the meshing surfaces, both said gear elements disposed in said housing;

(d) a discharge passage communicating between the interior and exterior of said housing;

(e) a porting arrangement comprising discharge ports in said internal ring gear element providing communication between said varying sized chambers and the periphery of said internal ring gear element, means rotating with said internal ring gear element for sealing said discharge ports as said varying sized chambers increase in size and for opening said discharge ports to communicate with said discharge passage as said varying sized chambers decrease in size, and inlet ports in said housing positioned to communicate with said varying sized chambers during increase in size.

3. In a rotary pump or motor, the combination of:

(a) a housing;

(b) a rotary external gear element;

(0) an internal gear element meshing with said external gear element to form varying sized chambers between the meshing surfaces, both said gear elements disposed in said housing;

(d) a discharge passage communicating between the interior and exterior of said housing;

(e) a porting arrangement comprising discharge ports in said internal ring gear element providing communication between said varying sized chambers and the periphery of said internal ring gear element, a flexible band around said internal ring gear element in contact with at least about half of the periphery of said internal ring gear element sealing said discharge ports communicating to the portion of said periphery of said internal ring gear element that is contacted by said flexible band and said flexible band being spaced from the remaining portion of the periphery of said internal ring gear element opening said discharge ports to communicate with said discharge passages, and inlet ports in said housing positioned to communicate with said varying sized chambers as said chambers enlarge.

4. In an internal gear pump or motor, the combination of: I

(a) a housing;

(b) an internal ring gear element having inwardly pro jecting teeth fixedly mounted in said housing;

() a shaft concentric with said internal ring gear element and rotatably mounted in said housing;

(d) an eccentric crank on said shaft and rotatable therewith;

(e) a pinion gear element rotatably mounted on said crank having outwardly projecting teeth of at least one less in number than said internal ring gear element, said pinion gear element having a planetary motion relative to said internal ring gear element upon rotation of said shaft thereby forming varying sized chambers between the inner surface of said internal ring gear element and the outer surface of said pinion gear element;

(f) a first annular passage and a second annular passage in isaid housing around said internal ring gear, said first annular passage communicating with a source of fluid exterior to said housing and said second annular passage open to the exterior of said housing;

(g) a communication passage in said internal ring gear element from the inner surface between each tooth to said first and second annular passages; and

(h) means disposed in each said communication passage for continuously and sequentially first, limiting said communication passage to communication between said inner surface of said internal ring gear element and said first annular passage, second, closing said communication passage, third, limiting said communication passage to communication between said inner surface of said internal ring gear and said second annular passage, and, fourth, closing said communication passage.

5. A pump structure comprising:

(a) a housing;

(b) an internal ring gear element having inwardly projecting teeth fixedly mounted in said housing;

(0) a shaft concentric with said internal ring gear element and rotatably mounted in said housing;

(d) an eccentric crank on said shaft and rotatable therewith;

(e) a pinion gear element rotatably mounted on said crank having outwardly projecting teeth of at least one less in number than said internal ring gear element, said pinion gear element having a planetary motion relative to said internal ring gear element upon rotation of said shaft thereby forming varying sized chambers between the inner surface of said internal ring gear element and the outer surface of said pinion gear element;

(f) a first annular passage and a second annular passage in said housing around said internal ring gear, said first annular passage communicating with a source of fluid exterior to said housing and said second annular passage open to the exterior of said housing;

(g) a communication passage in said internal ring gear element from the inner surface between each tooth to said first and second annular passages;

(h) a cylindrical plug disposed in each said communication passage having a first opening and a second opening through said plug, said plug being rotatably mounted; and

(i) means on said shaft connected to said plug for rotating said plug to a first position aligning said first opening with said communication passage and said first annular passage during increase in size of said varying sized chambers and to a second position aligning said second opening with said second annular passage during decrease in size of said varying sized chambers.

6. A pump structure comprising:

(a) a casing having a cavity;

(b) an intake duct and a discharge'duct communicating with the cavity of said casing;

(c) an outer annular rotor having a plurality of inwardly extending radial teeth disposed within said casing;

(d) an inner rotor having a plurality of outwardly projecting teeth meshing with said outer rotor to form a plurality of varying sized chambers between the outer surface of said inner rotor and the inner surface of said outer rotor;

(e) first fluid passages positioned around the periphery of said outer rotor and connected to said intake duct;

(1) second fluid passages positioned around the periphery of such outer rotor and connected to said discharge duct, each said second fluid passage being alternately arranged with said first fluid passages; and

(g) communication means positioned between the inwardly extending radial teeth of said outer rotor and communicating between the inner surface and the outer surface of said outer rotor, said communication means alternately communicating with a first fluid passage and then a second fluid passage during rotation of said rotors.

7. A pump structure comprising:

(a) a casing having a cylindrical bore;

(bl)j an inlet duct communicating with said cylindrical ore;

(c) a discharge duct communicating with said cylindrical bore;

(d) a plurality of intake ports and a plurality of discharge ports disposed around the inside surface of said cylindrical bore to form an annular port ring, said intake ports communicating with said inlet duct and said discharge ports communicating with said discharge duct and said intake ports being alternately arranged with said discharge ports in said annular port ring;

(e) an outer rotor having a plurality of inwardly extending radial teeth disposed within said annular port ring;

(1) an inner rotor having a plurality of outwardly extending radial teeth meshing with said outer rotor to form a plurality of varying sized chambers between the inner surface of said outer rotor and the outer surface of said inner rotor;

(g) communication means between successive teeth of said outer rotor, from the inner surface to the outer surface of said outer rotor; and

(h) indexing means for positioning said communication means to register with said discharge ports upon decrease in size of said varying sized chambers and with said intake ports on increase in size of said varying sized chambers.

8. A pump structure comprising:

(a) a casing having a cylindrical bore enclosed at each end by an end wall;

(b) an internal ring gear element having inwardly projecting teeth fixedly mounted in said housing; (0) a shaft concentric with said internal ring gear element and rotatably mounted in said housing; (d) a rotatable annular ring disposed within said cylindrical bore having its peripheral surface in sliding contact therewith, said annular ring including a plurality of discharge ports communicating from the inner surface of said annular ring to said discharge duct and a plurality of intake ports communicating from the inner surface of said annular ring to said intake duct, said intake ports being alternately arranged with said discharge ports in said annular ring;

(e) an outer rotor having a plurality of inwardly extending radial teeth, disposed within said annular ring with its peripheral surface in sliding contact therewith;

(1) an inner rotor having peripheral teeth at least one less in number than the teeth of said outer rotor, said inner and outer rotors being eccentrically mounted with respect to each other and with the teeth of one in constant sealing contact with the other to provide, together with said end walls, a series of sealed compartments of continuously varying dimensions constituting pumping chambers;

(g) a communicating passage from each of the valleys between said inwardly extending radial teeth to the periphery of said outer rotor; and

(h) indexing means connected to said annular ring for positioning said discharge ports to register with said communication passages upon reduction in size of said pumping chambers and for positioning said intake ports to register with said communication passages upon increase in size of said pumping chambers.

9. A pump structure comprising:

(a) a casing having a cylindrical bore enclosed at each end by an end wall;

(b) a first annular cavity in said casing communicating with said cylindrical bore;

() a second annular cavity in said casing communicating with said cylindrical bore;

(d) a discharge duct communicating with said first annular cavity;

(e) an inlet duct communicating with said second annular cavity;

(f) a rotatable annular ring disposed within said cylindrical bore with its peripheral surface in sliding contact therewith, said annular ring including a plurality of discharge ports communicating from the inner surface of said annular ring to said first annular cavity and a plurality of intake ports communicating from the inner surface of said annular ring to said second annular cavity, said intake ports alternately arranged with said discharge ports in said annular ring;

(g) an internal ring gear element having a plurality of inwardly extending radial teeth, said internal ring gear element disposed Within said annular ring with its peripheral surface in sliding contact therewith;

(h) a shaft having a crank, said shaft rotatably mounted in one of said end walls and having its axis coinciding with the center of said internal ring gear;

(2') a pinion gear element rotatably mounted on said crank having outwardly projecting teeth of at least one less in number than said internal ring gear element, said pinion gear element having a planetary motion relative to said internal ring gear element upon rotation of said shaft thereby forming varying sized chambers between the inner surface of said internal ring gear element and the outer surface of said pinion gear element;

(j) a communication passage in said internal ring gear element from the inner surface between each tooth to said first and second annular passages;

(k) a gear on said inner rotor meshing with a gear on said annular ring to index said communicating passages to register with said discharge ports upon reduction in size of said pumping chambers and to register with said intake ports upon increase in size of said pumping chambers.

10. A pump construction according to claim 9 wherein at least one of said end walls of said cylindrical bore are attached to and rotate with said pinion gear.

11. A pump construction according to claim 9 wherein at least one of said end walls of said cylindrical bore are attached to and rotate with said internal ring gear.

12. A pump construction according to claim 9 wherein at least one of said end walls of said cylindrical bore are attached to and rotate with said annular ring.

13. A pump structure comprising: (a) a casing including an inlet duct, a discharge duct,

14 and a cylindrical bore, said cylindrical bore enclosed at each end by an end wall on said casing;

(12) a crank supported by said housing;

(0) an annular ring disposed within said cylindrical bore, said annular ring including a plurality of discharge ports communicating from the inner surface of said annular ring to said discharge duct and a plurality of intake ports communicating from the inner sruface of said annular ring to said intake duct with said discharge ports being alternately arranged with said intake ports alternately disposed around said annular ring;

(d) an outer rotor having a plurality of inwardly extending radial teeth disposed within said annular ring with its peripheral surface in sliding contact with the inside surface of said annular ring;

(e) an inner rotor having peripheral teeth, said inner and outer rotors being eccentrically mounted with respect to each other and said inner rotor rotatably mounted on said crank so that the axis of the inner rotor rotates in one direction about the axis of the outer rotor as the inner rotor rotates in the opposite direction about its own axis with the teeth of one rotor in constant sealing contact with the teeth of the other to provide between the inner surface of said outer rotor and the outer surface of said inner rotor, together with the end walls on said housing, a series of sealed compartments constituting pumping chambers;

(f) a communicating passage from each of the valleys between said inwardly extending radial teeth to the periphery of said outer rotor; and

g) indexing means for positioning said discharge ports and communicating passages to register with each other during reduction in size of said pumping chambers and for positioning said intake ports and communicating passages to register with each other during increase in size of said pumping chambers.

14. A pump construction according to claim 13 wherein said annular ring is rotatably mounted and said outer rotor is fixedly mounted in said casing.

15. A pump construction according to claim 13 wherein said annular ring is fixedly mounted in said casing and said outer rotor is rotatably mounted.

16. A pump structure comprising:

(a) a casing including a cylindrical bore enclosed at each end by an end wall;

(12) a first annular cavity disposed in said casing and communicating with said cylindrical bore;

(0) a second annular cavity disposed in said casing and communicating with said cylindrical bore;

(d) a discharge duct communicating with said first annular cavity;

(e) an intake duct communicating with said second annular cavity;

( a plurality of separate ports fixed in said cylindrical bore between said first and second annular cavities arranged in the form of a ring, said ports including a plurality of alternately arranged discharge ports and intake ports communicating from the inner surface of said ring with said first annular cavity and said second annular cavity, respectively;

(g) an outer rotor having a plurality of inwardly extending radial teeth and disposed within said ring of ports with its peripheral surface in sliding contact with the inside surface of said ring of ports;

(12) an inner rotor having peripheral teeth at least one less in number than said outer rotor, said inner and outer rotors being eccentrically mounted with respect to each other and rotatably supported so that the axis of the inner rotor rotates in one direction about the axis of the outer rotor as said inner rotor rotates in the opposite direction about its axis causing said outer rotor to rotate in said opposite direction about its axis with the teeth of one rotor in 15 constant sealing contact with the other to provide between the inner surface of said outer rotor and the outer surface of said inner rotor, together with the end walls of said cylindrical bore, a series of sealed 19. A pump structure according to claim 18 wherein 16 end by an end wall and a fluid-discharge duct communicating with said cylindrical bore; (b) an outer rotor having a plurality of inwardly extending radial teeth and disposed within said cycornpartments constituting pumping chambers; lindrical bore with its peripheral surface spaced (i) a communicating passage from each of the valleys from the inner surface of said bore;

between said inwardly extending radial teeth to the (c) an inner rotor having peripheral teeth at least one periphery of said outer rotor; less in number than said outer rotor, said inner and (j) and a gear on said inner rotor meshing with a gear outer rotors being eccentrically mounted with respect on said housing to index said communicating pas- 0 to each other and with the teeth of one in constant sages to register with said discharge ports upon sealing contact with the teeth of the other to provide, reduction in size of said pumping chambers and to between the inner surface of said outer rotor and register with said intake ports upon increase in size the outer surface of said inner rotor together with of said pumping chambers. end plates at each end of said inner and outer rotors,

17. A pump structure according to claim 16 wherein a series of sealed compartments of continuously said end Walls of said cylindrical bore are aflixed to and varying dimensions constituting pumping chambers; rotate with said inner rotor. (d) a discharge port communicating from each valley l8. Apump structure comprising: between said inwardly extending radial teeth to the (a) a casing having an intake duct, a discharge duct, periphery of said outer rotor;

and a cylindrical bore enclosed at each end by an 20 (e) a flexible band around said outer rotor in contact end wall; with at least about half of the periphery of said (b) a plurality of ports afiixed to said cylindrical bore outer rotor to seal those said discharge ports that to form a ring, each said port having an opening communicate to the portion of the periphery of said toward the inner surface of said ring, said ports outer rotor that is contacted by said flexible band including first intake ports communicating with said and said flexible band being spaced from the remainintake duct, first discharge ports, second intake ports, ing portion of the periphery of said outer rotor opensecond discharge ports communicating with said ing said discharge ports to communicate with said discharge duct, and a distribution duct connecting cylindrical bore; and said first discharge ports and said second intake ports, (f) inlet ports positioned in one of said end walls to said first intake ports being adjacent said first discommunicate with said pumping chambers where charge ports and said second intake ports being adjasaid chambers are expanding. cent said second discharge ports; 22. A pump construction comprising:

(0) an outer rotor having a plurality of inwardly ex- (a) a casing having a cylindrical bore enclosed at each tending radial teeth and disposed within said ring of end by an end wall and a fluid-discharge duct comports with its peripheral surface in sliding contact municating with said cylindrical bore; with the inside surface of said ring of ports; (b) an outer rotor having a plurality of inwardly ex- (d) an inner rotor having peripheral teeth at least one tending radial teeth and disposed within said cylindriless in number than said outer rotor, said inner and cal bore with its peripheral surface spacedv from the outer rotors being eccentrically mounted with reinner surface of said bore; spect to each other and rotatably supported so that (c) an inner rotor having peripheral teeth at least one the axis of said inner rotor rotates in one direction less in number than said outer rotor, said inner and about the axis of said outer rotor as said inner rotor outer rotors being eccentrically mounted with respect rotates in the opposite direction about its axis causto each other and with the teeth of one in constant ing said outer rotor to rotate in said opposite direcsealing contact with the teeth of the other to provide, tion about its axis with the teeth of one rotor in between the inner surface of said outer rotor and the constant sealing contact with the other to provide outer surface of said inner rotor together with end between the inner surface of said outer rotor and the plates at each end of said inner and outer rotors, a outer surface of said inner rotor, together with said series of scaled compartments of continuously varyend walls of said cylindrical bore, a series of sealed ing dimensions constituting pumping chambers; compartments constituting pumping chambers; (d) a plurality of discharge ports each communicat- (e) a communicating passage from each said pumping ing from a valley between said inwardly extending chamber to the periphery of said outer rotor; radial teeth to the periphery of said outer rotor;

(f) the eccentric mounting and rotatable support being (:2) a first roller, a second roller, and a third roller furnished by a first gear aflixed to said inner rotor mounted in said cylindrical bore between said end meshing with a gear affixed to said housing indexing walls, said first roller and second roller being adjaeach said communicating passage to register with cent to the periphery of said outer rotor and said third first intake port upon increase in size of its assoroller spaced from the periphery of said outer rotor; ciated pumping chamber then to register with the (f) a flexible band around said outer rotor in contact adjacent first discharge port upon subsequent dewith at least half of the periphery of said outer rotor crease in size of its associated pumping chamber and, and spaced therefrom for the remaining portion, said upon continued rotation of said rotors, to register flexible band passing between said first roller and said with a second intake port upon increase in size of its outer rotor, around the periphery of said outer rotor, associated pumping chamber then to register with the between said second roller and said outer rotor, and adjacent second discharge port upon subsequent deover said third roller spaced from said outer rotor, crease in size of its associated pumping chamber. said flexible band sealing said discharge ports where in contact with said at least half of the periphery of said ring of ports includes a plurality of alternately disposed intake and discharge ports interconnected to provide multiple stages of fluid compression upon rotation of said rotors.

20. A pump construction according to claim 18 wherein said end walls of said cylindrical bore are affixed to and rotate with said inner rotor.

21. A pump construction comprising: (a) a casing having a cylindrical bore enclosed at each said outer rotor and said discharge ports being open to communicate with said cylindrical bore where said flexible band is spaced from the periphery of said outer rotor and being open where said pumping chambers reduce in size; and inlet ports in said end plates positioned to communicate with said pumping chambers where said pumping chambers increase in size.

23. A pump structure according to claim 22 wherein said end plates are attached to said inner rotor and rotating with said inner rotor, said inlet ports in said end plates are sealed by being opposite the ends of said inwardly projecting radial teeth where said pumping chambers reduce in size and communicate with said pumping chambers by being opposite said valleys where said pumping chambers increase in size.

References Cited in the file of this patent UNITED STATES PATENTS 18 Haight Dec. 10, 1929 Pigott Mar, 5, 1935 Pigott Sept. 8, 1936 Kleckner Nov. 26, 1940 Hill Jun 24, 1952 Mori Apr. 30, 1957 Schirmer et al Feb. 11, 1958 Nubling May 6, 1958 Patin Feb. 3, 1959 Insley Nov. 17, 1959 Brundage Oct. 18, 1960 FOREIGN PATENTS Germany Nov. 5, 1959 

1. IN A ROTARY PUMP OR MOTOR, THE COMBINATION OF: (A) A ROTARY GEAR ELEMENT; (B) AN INTERNAL RING GEAR ELEMENT MESHING THEREWITH TO FORM VARYING SIZED CHAMBERS BETWEEN THE OUTER PERIPHERY OF SAID ROTARY GEAR ELEMENT AND THE INNER SURFACE OF SAID INTERNAL RING GEAR ELEMENT; (C) A PORTING CONSTRUCTION COMPRISING A COMMUNICATION MEANS BETWEEN SUCCESSIVE TEETH OF SAID INTERNAL RING GEAR ELEMENT, SAID COMMUNICATION MEANS COMMUNICATING BETWEEN THE INNER SURFACE AND THE PERIPHERY OF SAID INTERNAL RING GEAR ELEMENT, AN ANNULAR RING CONTACTING THE PERIPHERY OF SAID INTERNAL RING GEAR ELEMENT, A PLURALITY OF DISCHARGE PORTS AND A PLURALITY OF INTAKE PORTS, SAID DISCHARGE PORTS BEING ALTERNATELY ARRANGED WITH SAID INTAKE PORTS IN SAID ANNULAR RING, AND MEANS ON SAID ANNULAR RING FOR POSITIONING A DISCHARGE PORT IN COMMUNICATION WITH EACH SAID COMMUNICATION MEANS ON DECREASE IN SIZE OF SAID VARYING SIZED CHAMBERS AND FOR POSITIONING AN INTAKE PORT IN COMMUNICATION WITH EACH SAID COMMUNICATION MEANS ON INCREASE IN SIZE OF SAID VARYING SIZED CHAMBERS. 